Metallurgical furnace



Jan. 26, 1932. H. J. HARTLEY .ET AL ,8

METALLURGICAL FURNACE Filed April 6, 1931 llllllflli 24m 16 WM Mrmd ATTORNEYS I Patented Jan, 26, 1932 DNITED STATES- PATENT OFFICE HENRY J. HARTLEY, OF HASTINGS-ON-HUDSON, AND FREDERICK B. SCHILLDN'G, F

FLUSHING, NEW YORK, AND GEORGE E. GONNOLLY, 0F OAKLAND, CALIFORNIA, AS- SIGNORS, BY MESNE ASSIGNMENTS, T0 NTECEOLS ENGINEERING AND RESEARCH CORPORATION, OF NEW YORK, N1. Y A CORPORATION OF DELAWARE METALLURGICAL FURNACE Application filed Apr-11' 8, 1981. Serial No. 528,018.

This invention. which relates to metallurgical furnaces has been shown in connection with the type of furnace including a series of superposed hearths so constructed that the treated material falls successively from hearth to hearth, and including also rotatable rabble arms for stirring the ore on the hearths and for feeding it toward the communicating passages between the hearths, as

in is the usual practice.

The invention .has for an object the provision of improved means for introducing air into the furnace whereby a more efiective and more complete. combustion or oxidation 13 may be obtained.

Another object of the invention is the provision of means for introducing fresh air, preferably preheated and substantially undiluted, over preferably evenly distributed to areas of the ore on one or more of the hearths, including means whereby the amount'of air introduced over the ore of the several hearths may be readily varied and may be made substantially uniform per unit area of the ore in a direction radially of the hearth.

The principle of the invention will be best understood from the following description taken in connection with the which Fig. 1 is a vertical section through a pertionof the furnace;

Figure 2 is a longitudinal horizontal section through one of the rabble arms showing one embodiment 9f an air-controlling means;

Fig. shows ahnodified form of air-controlling means Fig. 3 is a section on the line 3-3 of Fig. 2; andi Fig. 4 is a section on the line 4-4 of Fig. 2.

1n the drawings, Fig. 1 is a central vertical sectional View showing the outside wall of the furnace 5 and two hearthsti and 7, this being deemed sufficient to illustrate the principles of this invention. The hearths may communicate with each other alternately at drawings, in

their rims as at 8 and at their centers as at 9,

as is the usual practice. The furnace is provided with the usual flue, not shown, and may, if found desirable, be provided with the usual air inlet at the bottom of the furnace.

The furnace also includes rabble arms 10 carried by an outer hollow vertical rotatable shaft 11 and provided with inner tubes 12 whose inner ends project into an inner hollow vertical rotatable shaft 13. The outer end of the tube 12 is supported on triangularly arranged fins 14 on a closure member 15 for therabble arm 10.

Preferably, fresh air at normal outside temperature is forced upwardly through the inner tube 13, radially outwardly through the tube 12, out between the fins 14 into the concentric space between the rabble arm 10- and the tube 12 to cool the rabble arms 10.

A portion of the heated air in this space passes through air passages in tubes 16 carried by the rabble arm over the ore on the respective hearth while' the remainder, if desired, ma pass through apertures 17 in the inner eni of the rabble arm into the space between the rotatable shafts 11 and 13 and from" thence into the furnace through tubes 18 carried by the outer shaft 11, as shown, or a part of this air may be carried to outlets at the top or bottom of shaft 11.

As shown in Figs. 1 and 3, the rabble arm carries rabble teeth 20 secured to the under side portion 21, which is preferably a dovetail connecting means, cast integrally with the lower side of the rabble arm.

As shown in Figs. 1 to 3, one side of the rabble arm is provided with a plurality of apertures for receiving tubes 16 to carry the heated air from the space between the rabble arm 10 and the-tube 12 over the ore in the hearth. These tubes may be made of the same size and may be spaced uniformly along the length of the arm, or may be made of different sizes or spaced differently along the length of the arm, in order to get the roper distribution of the air over the ore 1n the hearth. By means of this construction fresh air is supplied at difierent closely prises a strip of metal 23 which is provided with laterally ofiset or depressed portions 24 adapted in the position shown in Fig. 2 to close the tubes 16 and to prevent any air from being fed over the ore on the hearth. The strip 23 may be supported on the tube 12 by means of one or more collars 25 slidably supported on the tube 12. The collar 25 and the strip 23 may be adjusted by means of a rod 26 which extends outwardly between the fins 14 through an elongated bearing in the closure member 15, for the purpose of controlling the amount of air admitted through the tubes 16. The valve mechanism may be ad justed b manipulating the rod 26 and may then be ocked in adjusted position by-means of pin 27 which extends through the bearing on the closure member 15 and through one of a plurality of semi-symmetrical grooves in the rod 26. 5

By means of the construction shown the amount of preheated fresh air delivered from the various rabble arms over the ore in the respective hearths may be controlled so as to get the proper amount of air in each hearth. Ifdesired, as shown in Fig. 1, the outer vertical rotatable tube 11 may be provided with tubes 18 through which preheated air may be blown into the stream of ore falling from alternate hearths.

As shown in Fig. 2a, the air-controlling portions 24a of the strip 23a may be so arranged with respect to the tubes 16 that a larger amount of air is delivered from the outer tubes than from the inner tubes thus providin for a more equal introduction of fresh pre eated air to the various concentric areas of the ore on the hearth.

The above described valve arrangement in some cases may be utilized for admitting fluids other than air into the roasting furnace at various desired hearths'in order to control combustion conditions, or in some cases to check excess combustion on certain hearths; for example, where the furnace is used in certain chemical processes, gases such as nitrogen, ammonia gas, etc. might be intro-.

duced through the valve outlets and distributed uniformly over the material under treatment by this arrangement, or if desired such gases could be admitted through only a part of the openings, or openings only at certain desired hearths.

It is obvious, of course, that the principle of this invention is applicable to other types of furnaces and that other modifications o the air-controlling means may be made within the spirit of this invention. Accordingly,

the terms used in the claimsare to be considered as terms of description rather than of.

and a valve mechanism comprising a strip of material provided with portions offset to lie in the planes of the inner ends of the tubesfor opening and closing said tubes.

2. In combination with a rabble arm comprising inner and outer spaced members, said outer member being provided with air passages, and a valve mechanism supported on the inner memberfor opening and closing said passages.

3. In combination with a'rabble arm coin-' prising inner and outer spaced members, said outer member being provided with air assages and a valve mechanism suppor on the inner member for opening and closing said assages, a closure element for the outer mem r, 'means thereon supporting the inner member, and means extending exteriorly through said closure member for operating said valve-mechanism.

4. In combination with a rabble arm comprising inner and outer spaced members, said outer member being providedwith air passages, a valve mechanism sup orted on the inner member for opening an closing said passages, a closure element for the outer member, means thereon supportin the inner member, means extending exterior y through said closure member for operating said valve mechanism, and means cooperating with said last mentioned means for locking said last mentioned means in adjusted position.

5. In combination with a rabble, arm comprising inner and outer spaced members, said outer member being provided with air passages, a valve mechanism supported on the inner member for opening and closing said passages, a closure element for the outer member, means thereon supporting the inner member, and a rod connected to said valve mechanism and extending exteriorly through said closure element.

6. In combination with a rabble arm comprising inner and outer spaced members, said outer member being provided with air passages, a valve mechanism supported on the inner member for opening and closing said passages, a closure element for the outer member, means thereon supporting the inner member, a notched rod connected to said valve mechanism and extending exteriorly' through said closure element, and a pin exf tending through said closure element and adapted to lie in .any-one'of'the series of,

notches in said rod for locking the valve mechanism in adjusted position.

7 In combination with a rabble arm comrising inner and outer spaced concentricaly arranged hollow members, said outer members being provided with air passages, a slidable valve mechanism common to said passages, a ring member slidably engaging said inner member for slidably supporting said up valve mechanism, and means extending exteriorly of said arm for operating said valve mechanism. 8. In a hollow rotatable rabble arm pro-. vided with an air chamber and apertures 35 establishing communication between said air chamber and a hearth, and a common means for controlling said apertures to control the amounts of air delivered at points along the length of the arm in direct proportion to the 2 distance of the apertures from the inner end of the arm. 7

9. A rabble arm construction comprising a hollow casing member, a conduit member extending longitudinally within said casing member, and spaced from the inside walls thereof, whereby fluid may be conducted into the rabble arm through said inner conduit member and discharged therefrom into the space between said members, said casing member being providedwith a pluralit of spaced fluid outlets along its length, ad usta le valve means for said outlets mounted within the space between said members, and means for holding said valve means against 85 longitudinal movement when in a plurality of different adjusted positions.

10. A rabble arm construction comprising a hollow casin member, aconduit member extending longitudinally within said casing 40 member and spaced from the inside walls thereof, whereby fluid may be conducted into the rabble arm through said inner conduit member and discharged therefrom into the space between said members, said casing '45 member being provided with a pluralit of s aced fluid outlets along its length, ad usta le valve means for said outlets mounted within the space between said members, and operating means attached to said valve means and extending at one end of said casing member to the exterior thereof for permitting operation and adjustment of said valve means from the exterior of the arm.

In testimony whereof we have signed our 7 names to this s ifieation.

HEN Y J. HARTLEY.

FREDERICK B. SCHILLING. GEORGE E. CONN OLLY. 

